Mr Hollande and Chancellor Angela Merkel of Germany called the revelations “unacceptable” with the German foreign ministry calling in the US ambassador to demand assurances that survelliance would be stopped.

“We cannot accept this kind of behaviour between partners and allies,” Mr Hollande said. “We ask that this immediately stop. There can be no negotiations or transactions in all areas until we have obtained these guarantees, for France but also for all of the European Union, for all partners of the United States.”

Germany also backed Mr Hollande’s threat to freeze talks launched last month at the G8 summit on $100 billion a year free trade talks between Europe and America stating that “mutual trust” was a necessary basis of negotiations.

“We aren’t in the Cold War anymore,” Steffen Seibert, Merkel’s chief spokesman, said. “If it’s true that diplomatic missions have been spied on, it would be absolutely unacceptable for us.”

Leaders set a deadline of the end of 2014 when the talks were launched, leading David Cameron to warn the ambitious timetable required strong political will to reach a far-reaching pact.

Mr Obama sought to defuse the growing row by promising to supply all the information requested by European allies regarding the spying allegations, which he said Washington was still evaluating.

He added: “Every intelligence service, not just ours, but every European intelligence service, every Asian intelligence service, wherever there’s an intelligence service, here’s one thing they’re going to be doing: they’re going to be trying to understand the world better and what’s going on in world capitals around the world from sources that aren’t available through the New York Times or NBC News.”

But Washington was facing protest of rare intensity across Europe with Mario Mauro, Italy’s defence minister, saying the US was treating its allies like Soviet satellite states.

Pleading the pressures of work as he negotiated in the Holy Land, Mr Kerry said he would “look into” the allegations properly before formally responding to the European protests.

The EU commission ordered a sweep of its headquarters and overseas offices for the presence of listerning devices.

Confidential documents made availabe by the fugitive CIA whistleblower Edward Snowden to the German magazine Der Spiegel said the US had monitored phone lines and bugged embassies of European countries. Britain was one of a handful of countries exempted. The allegations follow claims that GCHQ’s Tempora programme monitored European leaders.

One diplomatic insider said most countries made attempts to bug other states and that the row would blow over.

“It is part of the diplomatic game during negotiations,” said a former Brussels diplomat. “Everyone is being very shrill but most people assume others, even other EU allies, might well be listening. In the UN it is accepted channel of communication.”

Alexander Bortnikov, the head of Russia’s Federal Security Service, and Robert Mueller, the director of the FBI, to stay “in permanent contact” in an attempt to decide Edward Snowden’s fate.

Mr Snowden, a former CIA and US National Security Agency contractor, 30, is currently thought to be in a closed area of the transit and departures zone of Moscow’s Sheremetyevo airport after flying in there on June 23 from Hong Kong, where he leaked details of widespread surveillance by US security services of American citizens’ emails and telephone calls.

Ecuador, which initially suggested it could provide asylum to Mr Snowden, appears to have cooled on the idea.

Nicolas Maduro, the president of Venezuela, is currently visiting Moscow, prompting speculation that he could take Mr Snowden away. Mr Maduro earlier said that Snowden was almost certain to have his request approved if he asked for refuge in Venezuela.